Who are the site moderators, and what is their role here?

At Stack Exchange, we believe moderation starts with the community itself, so in addition to all users gaining privileges through reputation earned, each site has moderators elected through popular vote. We hold regular elections to determine who these community moderators will be (except in the case of new beta sites, which have moderators pro tempore, who are appointed by Stack Exchange staff). Moderators are elected for life, though they may resign (or, in very rare cases, be removed).

We generally expect that moderators:

are patient and fair

lead by example

show respect for their fellow community members in their actions and words

are open to some light but firm moderation to keep the community on track and resolve (hopefully) uncommon disputes and exceptions

Moderators are human exception handlers, there to deal with those exceptional conditions that could otherwise disrupt the community.

The most common moderator task is to follow up on flagged posts. Every post contains a small flag link, which anyone with 15 reputation can use. Posts can be flagged as spam, offensive, or just general “needs moderator attention” with an explanatory comment or link. Once flagged, a post increments a flag count that shows up in the topbar for every moderator.

If you see anything in the system that is evil, weird, or in any way exceptional and deserving of moderator attention for any reason…flag it! That’s the primary job of a moderator: to look at every flagged post, and take action if necessary.

Moderators also have some special abilities necessary to handle those rare exceptional conditions:

Moderator votes are binding. Any place we have voting — close, open, delete, undelete, offensive, migration, etc — that vote will reach the threshold and take effect immediately if a single moderator casts a vote.

Moderators can lock posts. Locked posts cannot be voted on or changed in any way.

Moderators can protect questions. Protected questions only allow answers by users with more than 10 reputation.

Moderators can see more data in the system, including vote statistics (but not ‘who voted for this post’) and user profile information.

Moderators can perform large-scale maintenance actions such as merging questions and tags, tag synonym approvals, and so forth.

A lot of the moderation work is mundane: deleting obvious spam, closing blatantly off-topic questions, and culling some of the worst-rated posts on the site. The ideal moderator does as little as possible, but those little actions may be powerful, visible, and highly concentrated.

If you have questions about the reasoning behind a moderator's actions, bring them up for discussion on meta. Remember to be constructive and polite; moderators have the best interest of the site in mind, but they may occasionally make mistakes or have to deal with controversial issues on which not everyone agrees.

Moderators act as a liaison between the community and Stack Exchange the company.

Site moderators can also escalate issues of moderation by contacting the Stack Exchange team for guidance and administrative or technical tasks.

Additionally, moderators can help draw extra attention to bugs, feature requests, or other issues that affect their site if the community is unable to resolve the issue on their meta site.

Site moderators are distinguished from normal users by the diamond (♦) displayed beside their user names. Some Stack Exchange employees also have diamonds next to their user names; these are usually developers or community managers, or other employees who work directly with our users to resolve bugs or address other community concerns. Stack Exchange employees identify themselves as such in their user profiles.